867 Installation and Programming Guide | Digital Monitoring Products
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ADDITIONAL INFORMATION
Wiring Specifications
DMP recommends using 18 or 22 AWG for all LX‑Bus and Keypad Bus connections. The maximum wire distance
between any module and the DMP Keypad Bus or LX‑Bus circuit is 1,000 feet. To increase the wiring distance, install
an auxiliary power supply, such as a DMP Model 505‑12. Maximum voltage drop between a panel or auxiliary power
supply and any device is 2.0 VDC. If the voltage at any device is less than the required level, add an auxiliary power
supply at the end of the circuit.
To maintain auxiliary power integrity when using 22‑gauge wire on Keypad Bus circuits, do not exceed 500 feet.
When using 18‑gauge wire, do not exceed 1,000 feet. Maximum distance for any bus circuit is 2,500 feet regardless of
wire gauge. Each 2,500 foot bus circuit supports a maximum of 40 LX‑Bus devices.
For additional information refer to the LX‑Bus/Keypad Bus Wiring Application Note (LT‑2031) and the 710 Bus
Splitter/Repeater Module Installation Guide (LT‑0310).
Power Supply
The bell power must be supplied by a regulated, power limited, auxiliary power supply listed for Fire Protective
Signaling with a maximum output of 5 Amps at 12 or 24 VDC. The power supply output positive connects to module
Terminal 1 and power supply output negative connects to module Terminal 2.
The power supply must be supervised and provide a set of Normally Closed trouble contacts that connect to the
Power Supply Monitor zone (Terminals 7 and 8) on the 867 module. An open on the supervision circuit causes the
Power Supply Monitor LED to light and an open condition to be reported on the panel supervisory zone address.
LED Operation
For normal operation, all notification devices are connected in parallel on the Style W circuit. An included 10k Ohm
EOL resistor installs at the last device in the circuit. The Style W circuit LED operation is defined as follows:
▶
Normal—No LEDs light and the module reports a normal condition on the supervisory zone address.
▶
Open or Short—The TRBL LED lights and the module reports an open condition on the supervisory zone
address.
▶
Ground Fault—The TRBL and GND FAULT LEDs light and the module reports an open condition on the
supervisory zone address.
Bell Silence Switch
The Bell Silence slide switch allows technicians to test or perform maintenance on the fire system without sounding
the fire alarm notification devices. When the switch is placed in the Bell Silence position, the module TRBL LED turns
on and an open condition is reported on the supervisory zone address. After testing, returning the silence switch to
the Bell Normal position returns the module to normal operation.
